3DSky often uses commercial textures (Arroway/Evermotion,etc..). Some of the models shouldn't be uploaded or sold but hey....Russians. Then the model happens to get into another commercial package, multiplying this resourceful effect, re-selling someones-else stuff for second time. I guess it might continue..
Well, to be fair 3dSky admins started cleaning out models with non-transferable assets used, even banned some accounts. Intellectual property concept is very young in Russia.
It's actually a very funny story. 3dSky was started initially as a sharing resource for pros, with a tiny bit of income on the side. You upload 15 pro models per year, you get a pro account with unlimited free downloads for everything. A beautiful idea. Little did they know. Russian designers, who can't be bothered with modeling scenes properly, or paying someone else to do it, started hiring modelers to get them pro accounts and endless flow of free assets. Hired modelers were too lazy to actually model something, so they started to reiterate on older 3dSky assets(!), using ffd or different textures or just uploading 5 cushions, that take 20 minutes in MD. And the library is so big now, that it's nearly impossible to detect a duplicate. Now they have a shitfest thread on their forums a billion pages long, consisting of mutual accusations from artists, copyright violation claims, pointing at 3rd party assets, and admins reporting bans. It's a fascinating reading.